The invention relates to an apparatus for feeding one or more ingredients of a free-flowing bulk material to a proportioning apparatus, the proportioning apparatus having a number of hopper scales corresponding to the number of the ingredients, one for each of the ingredients. The hopper scales are disposed above the proportioning apparatus, and a dispensing spout equipped with a shutter to open and close it, is associated with each hopper scale.
Such apparatus are used, for example, on plastic fabricating machines, such as injection molding or extruding apparatus, for the precisely controlled feeding of bulk material. The known feeding apparatus have a supporting plate disposed above the hopper scales, in which are held all feed spouts and shutters for the feeding of a material consisting of individual ingredients. A disadvantage in the known feeding apparatus is that, since the number, arrangement and size of the hopper scales are different and are adapted to the material they feed, an individually fitted supporting plate with corresponding bores for the feed spouts and shutters must be provided for each of the different proportioning apparatus. For one thing, this increases the manufacturing cost of the known apparatus, and on the other hand any eventual change in the material to be fed, and thus in the proportioning apparatus, is possible in many cases only with additional expense, and this undesirably limits the flexibility of such apparatus.